Sawgrass above ground biomass from the Taylor Slough, Everglades National Park (FCE), South Florida from August 1999 to Present

Sawgrass biomass is measured for TS/Ph-1, 2, 3, & 6 since 1999; TS/Ph-4 & 5 since 1997 to 2006; SRS-1b, 2, & 3 since 2000; SRS1c for 2005 to 2006, and SRS1d since 2006. Three 1 m2 plots are placed on each site. The sites are measured every two months. The number of sawgrass plants is counted for each 1 m2 plot and one third or a minimum of fifteen plants is measured. For each measured plant, measurements of the total number of live leaves, length of the live leaves, and culm diameter at the base are taken. From these measurements we calculate the average leaf length, and the sum of the length of the leaves. We created a model for biomass using a stepwise regression to see which of the variables measured and calculated are more correlated to explain plant biomass. Obtaining the mean biomass for the plants within the plot and multiplying it by the number of plants counted in the plot calculates biomass for each plot. The total biomass for each plot is summed with the other two plots in the same site, and they are averaged to obtain one biomass number per site. To validate our model, plant clippings are obtained in which four plants are clipped (small, medium, large, inflorescence) from each site. The same measurements are applied to the clipped plants as those applied to the measured plants in the plots. The plant clippings are oven dried at 70 degrees C and weighed.

自1999年起，对TS/Ph-1、2、3及6号样地开展锯草（sawgrass）生物量（biomass）测定；TS/Ph-4、5号样地的测定时段为1997年至2006年；SRS-1b、2、3号样地自2000年起开展测定；SRS1c号样地的测定周期为2005年至2006年，SRS1d号样地自2006年起开展测定。每个样地布设3个1㎡样方，每两个月对样地进行一次测定。针对每个1㎡样方，统计其内锯草植株总数，并选取其三分之一且不少于15株进行详细测量。对每株被测植株，记录活叶总数量、活叶长度以及茎秆基部直径三项指标。基于上述实测数据，我们计算得到单株平均叶长与单株总叶长之和。我们采用逐步回归（stepwise regression）构建生物量预测模型，以筛选与植物生物量相关性最强的实测变量与计算变量。先计算单个样方内植株的平均生物量，再乘以该样方内统计的植株总数，即可得到该样方的生物量。将同一样地内3个样方的总生物量求和后取算术平均，最终得到该样地的生物量数值。为验证所构建的模型，我们从每个样地采集4株锯草植株（分别为小型、中型、大型植株及花序），采用与样方内被测植株完全一致的测量流程对其进行测定。将采集的植株样品置于70℃烘箱中烘干并称重。